1. Field of the Invention
The present invention relates to a full-color plasma display panel, and more particularly, to a full-color plasma display panel that uses different discharge gases to emit different colored light.
2. Description of the Prior Art
Full-color plasma display panels (PDP) that use discharge gases to emit multi-colored light are a well-known type of planar display in the field. The luminous performance of the PDP is similar to that of millions of flat-shaped, minute fluorescent lights of various colors. The known PDP comprises phosphor materials that coat tiny discharge cells. The dimensions of these cells can be on the order of a few hundreds of microns. The cells are filled with a discharge gas made from neon (Ne) and xenon (Xe), or helium (He) and xenon (Xe). When excited, the discharge gas emits ultraviolet radiation. This irradiates the phosphor materials, which then emit red light, green light or blue light.
Please refer to FIG. 1. FIG. 1 is a perspective view of a full-color PDP 10 according to the prior art. The prior art full-color PDP 10 comprises a first substrate 12, a second substrate 14 parallel to the first substrate 12, a discharge gas (not shown) that fills the space between the first substrate 12 and the second substrate 14, a plurality of first electrodes 18, a plurality of second electrodes 20, and a plurality of third electrodes 22. The first electrodes 18 and the second electrodes 20 are positioned on the first substrate 12 in parallel and at regular intervals. Each of the third electrodes 22 are positioned on the second substrate 14 and are orthogonal to the first electrodes 18 and the second electrodes 20. Each of the first electrodes 18 and the second electrodes 20 comprises a maintaining electrode 181, 201, respectively, made of ITO materials, and an auxiliary electrode 182, 202, respectively, made of a Cr/Cu/Cr metal alloy. The maintaining electrode 181, 201 has high resistance and poor conductivity, but is transparent to visible light. The auxiliary electrode 182, 202 has a low resistance, and so increases the conductivity of its respective electrode 18, 20.
The full-color PDP 10 further comprises a dielectric layer 24 that covers the surfaces of the first substrate 12, the first electrodes 18 and the second electrodes 20. A protective layer 26 covers the dielectric layer 24. A plurality of barrier ribs 28 are positioned in parallel on the second substrate 14, and isolate adjacent third electrodes 22 to define a plurality of discharge spaces 30. A phosphor layer 32 coats the third electrode 22 and the barrier rib 28 within each discharge space 30. The phosphor layer 32 under radiation may emit either red light, green light or blue light. Each of the discharge spaces 30 is part of a plurality of unit display elements 34, which are a specific region defined by one of the first electrodes 18, one of the second electrodes 20, and one of the third electrodes 22. When an initiating voltage is induced between the first electrode 18 and the third electrode 22, an electric field results in ionization of the discharge gas between the first electrode 18 and the third electrode 22 and charges form on the walls. The first electrode 18 and the second electrode 20 drive the plasma formed in the unit display element 34 in an alternating fashion, causing it to continuously emit ultraviolet radiation. Under this ultraviolet radiation, the phosphor layer 32 emits light of a predetermined color, and this light is passed on to a user through the transparent first substrate 12.
The color of the light emitted from the phosphor layer 32 depends upon the phosphor materials used. When ((Y,Gd)BO3) is applied to the phosphor, and Eu is added as an activating agent, the phosphor layer 32 will emit red light. When Zn2SO4is applied to the phosphor, and Mn is added as an activating agent, the phosphor layer 32 will emit green light. When BaMgAl14O23 is applied to the phosphor, and Eu is added as an activating agent, the phosphor layer 32 will emit blue light. However, the fabrication process of the phosphor materials is complicated, and the price of these materials is not cheap. Additionally, the red light emitted from the phosphor layer 32 lacks color purity. The green light emitted from the phosphor layer 32 is too persistent. The blue light emitted from the phosphor layer 32 suffers from color degradation over time. Finally, the phosphor layer 32 coated within the discharge space 30 is easily damaged by plasma bombardment, which shortens the usable life of the full-color PDP 10.
It is an object of the present invention to provide a full-color PDP that uses different discharge gases to emit specifically colored light, and which doesn""t use phosphor materials, so as to avoid the above-mentioned problems.
In accordance with the claimed invention, the present invention PDP comprises a back substrate, and a front substrate positioned on the back substrate. A space is formed between the facing surfaces of the back substrate and the front substrate. A plurality of barrier ribs is positioned within the space for defining a plurality of discharge space groups. Each group comprises a first discharge space, a second discharge space, and a third discharge space, wherein each discharge space comprises an upper opening on an upper side of the discharge space and a lower opening on a lower side of the discharge space. Furthermore, a plurality of air-locking ribs are positioned within the space to seal the lower opening of the first discharge space, the upper opening and lower opening of the second discharge space, and the upper opening of the third discharge space. A first wall is positioned on an upper side of the plurality of the discharge space groups, wherein the first wall and the adjacent air-locking ribs define a first channel which is accessible through each of the upper openings of the first discharge spaces. A second wall is positioned on a lower side of the plurality of the discharge space groups, wherein the second wall and the adjacent air-locking ribs define a second channel which is accessible through each of the lower openings of the third discharge spaces. In addition, a first gas, a second gas, and a third gas respectively fill the first discharge space, the second discharge space, and the third discharge space to emit different colored light.
It is an advantage of the present invention that the PDP, without phosphor materials, uses different discharge gases as light sources, so the problems associated with phosphor materials are avoided, and the useable lifetime of the PDP is increased.
These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after having read the following detailed description of the preferred embodiment which is illustrated in the various figures and drawings.